So for my first project, I was thinking about measuring the waterlevel in our pond. But when our diesel tanks went empty again, it seemed to be a better idea to measure them instead. It has happened before, they went empty to the bottom and that's not a very good thing.
So there you have it, my first Arduino project. As you might know, the book Practical Arduino does even have a project on that subject. But it uses pressure for measuring and I want to use sonar. Why? because that way you don't have to put anything in the Liquid (water, diesel, fuel, ...).
Now the first thing I'll have to do do, is make up my mind on what I want as a result for the project. So let's so.
- Measure the level in 2 separate tanks
- Show me the actual level in %
- Let me know when the level hits 50%, 20% and something like 5%
- log all the levels, so we can see the evolution of the levels.
Doesn't seem to be that hard. But first lets have a better look on those 3 points. Measuring 2 separate tanks means we'll need 2 sensors and that we will have 2 outputs. No problem there, I guess. The show me part is what me still bothers. How do I won't it to be shown? One show the results on the Arduino serial monitor, show the level on an LCD screen, or you could show the level on a website. Sending the level to serial, doesn't seem to be a good way (well it is for testing purpose). Only having a LCD screen means, you have to go check the LCD screen (where ever you put it) and only having a website, means you'll have to check a website, even when you're next to the tanks. So a combination of both would be the best. We also want to the Arduino to warn us, when a certain level has been reached. We could use twitter, sms, email or even a call. I would go for email. And finally we want to log all levels. That can be done on the Arduino, or on a dedicated server, which might be the better choice, because maybe later we want to log some other data as well.
Yet another decision to make, should the level showing website be on the Arduino or on an other website. I would prefer a different webserver for the same reason as above. It is much easier to check one website with all our info, than having to check several Arduino's. All these things put together, made my decision to have several projects out of this one problem: Measuring e tank level.